It's increasingly obvious that Mitt Romney's "second interview" to become the Conservative Alternative to McCain and Giuliani in the GOP presidential contest is working out a lot better than his first. Having jumped into a lead or strong second place in several recent polls in NH, the Mittster is now moving up fast in Iowa as well. Via TPMCafe's Election Central, we learn that Romney's opened up a surprisingly big lead in the latest Iowa Poll by the Des Moines Register. Among likely caucus-goers, he's at 30%, with McCain at 18%, Giuliani at 17%, and nobody else in double digits (the poll does not include Fred Thompson or Newt Gingrich).

In both IA and NH, Romney seems to be benefitting from his recent ad blitz, and from the troubles of his top-tier rivals.

On the Democratic side, the Register poll has John Edwards maintaining his lead at 29%, with Obama (23%) edging ahead of Clinton (21%) for second place, and Bill Richardson hitting double digits at 10%. In general, recent polls in Iowa and NH show a relatively stable three-way race among Edwards, Clinton and Obama, with Richardson (whose own recent ads have been well-received) overcoming his questionable debate performances to occupy the second tier by himself.

UPDATE: The most immediate threat to Romney's new elevated status remains a Fred Thompson candidacy. And just this weekend, supporters of the Tennessean got a symbolic boost when he trounced the field in a straw poll of 429 delegates held at the Georgia Republican State Convention. As the Atlanta Journal-Constitution's Political Insider blog reports, Thompson pulled 44%, with Gingrich at 18%, Giuliani at 15%, Romney at 9%, and McCain way down at 2%. It's also worth noting that Fred's running even with Romney in recent polls of Florida.